Enclosed switchboard

ABSTRACT

An enclosed switchboard includes: a device containing board which contains main circuit devices such as circuit breakers; and a cable connection board which is arranged side by side adjacently to the device containing board, and contains cables that input and output electric power to/from the main circuit devices. In the enclosed switchboard, the cable connection board is configured by one housing; and the inside of the housing is divided into two by a partition plate to be comparted to a cable lead-in compartment which contains lead-in side cables and a cable lead-out compartment which contains lead-out side cables.

This application is a Divisional of U.S. application Ser. No. 14/126,724filed on Dec. 16, 2013, which is a National Stage of InternationalApplication No. PCT/JP2012/063860 filed on May 30, 2012, which claimsthe benefit of Japanese Application No. 2011-166375 filed on Jul. 29,2011, Japanese Application No. 2011-168998 filed on Aug. 2, 2011, andJapanese Application No. 2011-196815 filed on Sep. 9, 2011. Thedisclosures of the prior applications are hereby incorporated byreference herein in their entirety.

TECHNICAL FIELD

The present invention relates to an enclosed switchboard in which aplurality of boards including a dedicated board for cable connectionprocessing are arranged side by side and, more particularly, relates tothe structure of a cable connection board, the structure of an enclosedswitchboard which reduces damage due to fire and water disaster, and afixing structure which fixes a floor portion of an enclosed switchboardrequired for aseismic performance.

BACKGROUND ART

In the structure of a conventional enclosed switchboard arranged side byside, main circuit cables for lead-in and lead-out are connected toindividual housings (boards), respectively, as shown in FIG. 17. Morespecifically, in a conventional unit configuration, a cable lead-inboard 81 which leads in cables, a circuit breaker containing board 82 inwhich circuit breakers and the like are contained, and a cable lead-outboard 83 which leads out cables are arranged side by side from the leftside of FIG. 17. In this manner, lead-in cables and lead-out cables areindividually contained in two different housings, respectively.

Incidentally, there is a case where a box for connecting cables isprovided on the upper portion of an enclosed switchboard, and cables areconnected in the box.

Furthermore, for example, there is a generally known switchboard whichis configured such that a plurality of circuit breakers are arranged upand down in a circuit breaker compartment provided on the front side ofthe inside of a housing, a main busbar compartment and a cablecompartment are provided behind the circuit breaker compartment, one endside of each circuit breaker is connected to a main busbar disposed inthe main busbar compartment, and the other end side is connected to aload cable in the cable compartment to be led out to the outside (forexample, see Patent Document 1).

Besides, the following technique is disclosed as the configuration of aswitchboard which takes into account disaster prevention against firedisaster or the like. For example, in a conventional enclosedswitchboard shown in FIG. 6 of Patent Document 2, circuit breakers,cables, devices such as busbars are contained in a circuit breakercompartment, a cable compartment, and a busbar compartment,respectively; and each compartment is partitioned by a grounding metal.Furthermore, in a conventional enclosed switchboard shown in FIG. 1 ofPatent Document 2, the enclosed switchboard is divided into three blocksof a cable compartment, a busbar compartment, and a circuit breakercompartment; a partition plate is provided in a boundary between thecable compartment and the busbar compartment; air ducts communicatedwith other are provided in a boundary between the busbar compartment andthe circuit breaker compartment and on the lower portion and the upperportion of the enclosed switchboard; a gradient is formed in the airduct of the upper portion; and a fan is provided in an exit of the airduct. Further, a thermoelectric element is provided at a boundary withthe air duct on the upper portion of the cable compartment, the busbarcompartment, and the circuit breaker compartment.

By such a configuration, indoor air whose temperature rises duringenergization is released to the outside with a fan while exchanging heatby the thermoelectric element; and the enclosed switchboard is dividedinto several blocks to prevent fire spread to other blocks even when afire disaster occurs.

Furthermore, in other conventional enclosed switchboard disclosed inPatent Document 3, there is a structure in which, in the enclosedswitchboard in which a plurality of boards are arranged side by side asshown in FIGS. 18 and 19, two partition plates 90 of grounding metal areprovided between the adjacent enclosed switchboards and a fire-retardantplate 88 and a gasket 89 are inserted over the whole surface between thepartition plates 90; and thus, heat to adjacent circuit breaker boardsis blocked to prevent the spread of a fault in the case of fire disasterin the circuit breaker board.

Besides, as the fixing structure of a conventional switchboard whichtakes into account seismic adequacy, for example, a fixing device likeFIG. 20 is known. FIG. 20A is a perspective view of a floor fixingportion; and FIG. 20B is a side sectional view in which FIG. 20A is seenfrom an arrow direction b. The configuration is made such that, amongframes that constitute a housing of the switchboard, a thick flat plate92 thicker in thickness than a base portion frame 91 is fixed at acorner portion of the base portion frames 91 by being welded to a rightangle portion coming into contact on the same flat surface, a foundationbolt 93 embedded in the floor is made to pass through an attaching hole92 a formed in the thick flat plate 92, and clamping is made by a nut 95via a washer 94 from the upper side; and thus, the switchboard is fixedto a foundation surface (see Patent Document 4).

PRIOR ART DOCUMENT Patent Document

[Patent Document 1] Japanese Unexamined Patent Publication No.2008-43181 (Page 2, FIG. 1)

[Patent Document 2] Japanese Unexamined Patent Publication No. H3-256507

[Patent Document 3] Japanese Unexamined Utility Model Publication No.S63-160004

[Patent Document 4] Japanese Utility Model Publication No. S58-21285(Page 2, FIGS. 3 and 4)

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

In the enclosed switchboard in which a plurality of enclosedswitchboards are arranged side by side, lead-in and lead-out cables maybe a charged portion and a non-charged portion, respectively, in thestructure of the housing of the conventional enclosed switchboard; andtherefore, a cable is considered to be separated in order to securesafety during work and the lead-in and lead-out cables are arranged inindividual housings, respectively. Such a configuration has a problem inthat a wide space is needed as a cable processing space; andaccordingly, the whole outside dimensions become large when the enclosedswitchboards are arranged side by side and an installation area of abuilding in which the enclosed switchboards are arranged becomescommensurately large.

Besides, in the configuration in which the box for connecting cables isarranged on the upper portion of the housing without providing adedicated housing for cable connection in order to reduce an arrangementspace, a large and heavy box is placed on the upper portion of thehousing, and accordingly, the center of gravity is elevated and aseismicperformance lowers and an aseismic reinforcement needs to be provided inthe case where aseismic performance is required.

Further, as in Patent Document 1, in the switchboard of theconfiguration in which the cable compartment for lead-out cables isarranged behind the circuit breaker compartment, a problem exists inthat a board for cable lead-in needs to be separately provided.

Furthermore, as for an enclosed switchboard which takes into accountdisaster prevention against fire disaster or the like, partitionmechanisms between the circuit breaker compartment and the busbarcompartment, between the busbar compartment and the cable compartment,between the circuit breaker compartment and the cable compartment, andbetween the circuit breaker boards are not sufficient in theconventional example of Patent Document 2; and in the case where thepartition plate is burnt out and melted by heat due to flames when afire disaster occurs, there is a possibility to bring large damage to acompartment other than a compartment in which the fire disaster occurs.In addition, in the conventional example of Patent Document 3, a problemexists in that the structure is complicated and it becomes high cost.

Moreover, a problem is to provide a structure in which water is notintruded into an important circuit even when water is partially intrudedinto the circuit breaker board and the circuit breaker board can berecovered promptly.

Besides, in the conventional fixing structure shown in Patent Document 4as the conventional enclosed switchboard which takes into accountseismic adequacy, the thick flat plate 92 is welded and fixed to thebase portion frames 91 at four corners of the housing as the members formounting the foundation bolt. However, a problem exists in that thethick flat plate 92 is individually provided at each corner; andaccordingly, the strength of the fixing portion is not necessarilysufficient and the base portion frame 91 is likely to be deformeddepending on large vibrations due to an earthquake or the like, theweight and the position of the center of gravity of the switchboard, andthe like.

Furthermore, when the thick flat plate 92 is welded, welding isdifficult to keep the distance between bolt holes within tolerance inaccordance with dimensions between the left and right foundation boltsand between the front and back foundation bolts, and it also takesworking time. For this reason, generally, the hole diameter of theattaching hole 92 a is a larger size or a longer hole than a standardbolt hole of the corresponding foundation bolt 93 taking into accountattaching errors and manufacturing errors of components and clamping ismade by means of a large diameter and thick special washer; andaccordingly, the special washer is needed.

The invention has been made to solve the problem described above, and anobject of the present invention is to obtain an enclosed switchboardcapable of reducing an installation area even when a dedicated board forcable lead-in and lead-out is provided.

Moreover, an object of the invention is to minimize damage due to fireand water disaster by improving separation performance of a circuitbreaker board with the aim of improving disaster prevention property.

Furthermore, an object of the invention is to obtain an enclosedswitchboard which enhances rigidity of a fixing portion to be fixed to afoundation and improves seismic adequacy.

Means for Solving the Problems

According to the present invention, there is provided an enclosedswitchboard including: a device containing board which contains maincircuit devices; and a cable connection board which is arranged side byside adjacently to the device containing board, and contains cables thatinput and output electric power to/from the main circuit devices. In theenclosed switchboard, the cable connection board is configured by onehousing; and the inside of the housing is divided into two by apartition plate to be comparted to a cable lead-in compartment whichcontains lead-in side cables and a cable lead-out compartment whichcontains lead-out side cables.

Moreover, there is provided an enclosed switchboard including a housingwhich includes: a circuit breaker compartment which contains circuitbreakers stacked in upper and lower stages; a busbar compartment whichcontains busbars connected to each of the circuit breakers; and upperstage and lower stage cable compartments each of which contains cablesconnected to each of the circuit breakers. The circuit breakercompartment is arranged, and the busbar compartment and the upper stageand lower stage cable compartments are arranged behind the circuitbreaker compartment. In the enclosed switchboard, the housing isarranged in plural rows, and includes air heat insulation layers forshielding heat. Each of the air heat insulation layers is provided:between both adjacent side walls of the housings disposed in parallel;on a ceiling portion of the circuit breaker compartment; on a partitionportion between the circuit breakers stacked in stages; on a partitionportion between the upper stage cable compartment and the lower stagecable compartment; and on a back wall portion of the circuit breakercompartment, the back wall portion coming into contact with the busbarcompartment and either one or both of the upper stage and lower stagecable compartments.

Furthermore, there is provided an enclosed switchboard including ahousing whose outline is formed in a substantially cuboid shape bycombining a vertical frame, a width directional frame, and a depthdirectional frame. In the enclosed switchboard, the housing includes: apair of vertical frames arranged in face-to-face relation on the leftand the right in the width direction of the housing; a floor side widthdirectional frame provided so as to connect the lower sides of thevertical frames; and a reinforcing member for fixing the housing. Thereinforcing member is made of a plate thicker than the thickness of eachof the frames and has a length whose both ends come into contact withthe pair of the vertical frames, and the reinforcing member is arrangedon a floor plate of the housing and fixed to the lower sides of the pairof the vertical frames and the floor side width directional frame bywelding.

Advantageous Effect of the Invention

According to the enclosed switchboard of present invention, the cableconnection board is configured by one housing and the inside of thehousing is divided into two by the partition plate to be comparted tothe cable lead-in compartment which contains lead-in side cables and thecable lead-out compartment which contains lead-out side cables; andtherefore, the lead-in side cables and the lead-out side cables arecontained in the same housing. Consequently, as compared to the casewhere the lead-in side cables and the lead-out side cables are containedin individual housings, cable connection processing can be performed inone side; and therefore, connection work can be easily performed and aninstallation space of the enclosed switchboard can be reduced.

Moreover, the heat insulation layers is provided between the frontcircuit breaker compartment and each of the respective back compartmentsand between the circuit breaker boards, whereby separation performanceof the respective compartments and the circuit breaker boards can beenhanced and heat due to flames on the occurrence of fire disaster inthe circuit breaker board can be prevented from being transmitted andspread to other circuit breakers and other compartments. In addition,combination use with the metallic barrier is easy and therefore theeffect of heat blockage can be further improved.

Furthermore, the reinforcing member for fixing the housing, thereinforcing member being made of a thicker plate and having a lengthwhose both ends come into contact with the pair of the vertical frames,is arranged on the floor plate of the housing and fixed to the lowersides of the pair of the vertical frames and the floor side widthdirectional frame by welding, whereby rigidity of the floor of theenclosed switchboard can be enhanced and the enclosed switchboardexcellent in seismic adequacy can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side-by-side board configuration view in which an example ofan enclosed switchboard with a unit configuration by a side-by-sideboard arrangement according to Embodiment 1 of the present invention isshown in a block skeleton;

FIG. 2 is a perspective view showing an external appearance of theside-by-side board configuration of FIG. 1;

FIG. 3 is a single line diagram for explaining the configuration ofcable lead-in and lead-out portions of the enclosed switchboardaccording to Embodiment 1 of the present invention;

FIG. 4 is an internal structure view of a cable connection board of theenclosed switchboard according to Embodiment 1 of the present invention;

FIG. 5 is a view showing the internal structure of a circuit breakercontaining board which is arranged side by side to a cable connectionboard according to Embodiment 1 of the present invention;

FIG. 6 is a side view of a cable connection board of an enclosedswitchboard according to Embodiment 2 of the present invention;

FIGS. 7A and 7B show the whole of an enclosed switchboard according toEmbodiment 3 of the present invention, FIG. 7A is a side sectional view,and FIG. 7B is a back view in which laterally disposed two enclosedswitchboards are seen from the back;

FIG. 8 is a side sectional view showing a metallic barrier portion ofthe enclosed switchboard according to Embodiment 3 of the presentinvention;

FIG. 9 is a front view in which FIG. 8 is seen from the front;

FIG. 10 is a back view in which FIG. 8 is seen from the back;

FIG. 11 is a perspective view of a housing of an enclosed switchboardprovided with a board fixing structure according to Embodiment 4 of thepresent invention;

FIG. 12 is a detail view of a portion A of FIG. 11 and is a partialperspective view in a state where a reinforcing member is not present;

FIG. 13 is a perspective view of the reinforcing member to be used inFIG. 11;

FIG. 14 is a perspective view in which the reinforcing member of FIG. 13is combined with the partial perspective view of FIG. 12;

FIG. 15 is a sectional view of a foundation bolt portion in which afixing portion of the enclosed switchboard according to Embodiment 4 isfixed to a foundation;

FIG. 16 is a sectional view showing other example of the foundation boltportion;

FIG. 17 is a single line diagram for explaining the configuration ofcable lead-in and lead-out portions of a conventional switchboard;

FIG. 18 is a side sectional view showing an example showing aconventional technique provided with a fire-retardant plate;

FIG. 19 is a partial sectional view in which the structure betweencircuit breaker boards of FIG. 18 is shown in detail; and

FIG. 20A is a perspective view and FIG. 20B is aside sectional view,each showing a fixing device of the conventional switchboard.

MODE FOR CARRYING OUT THE INVENTION

First, the whole configuration of an enclosed switchboard in which aplurality of switchboards each contained in a metal case are arrangedside by side. FIG. 1 is the side-by-side board configuration view inwhich an example of a unit configuration of an enclosed switchboard isshown in a block skeleton; and FIG. 2 is a perspective view showing anexternal appearance of the enclosed switchboard configured as shown inFIG. 1.

Incidentally, the enclosed switchboard to be an object of the presentapplication is equivalent to one which is ordinarily referred to asswitchgear; and therefore, a term is standardized to “enclosedswitchboard” in the present invention.

In FIG. 1, the unit is configured from the left side by a cableconnection board 100 which receives electric power supply by cables froman upper system, a circuit breaker containing board 200 in which circuitbreakers VCB are contained, and feeder boards 300 and 400 which supplyelectric power to a feeder via two circuit breakers VCB connected to thecircuit breaker containing board 200 and main busbars. Incidentally, theunit configuration of the drawing is typically shown, but not limited tothis.

As shown in the perspective view of FIG. 2, each board which constitutesthe enclosed switchboard contains circuit breakers, busbars, cables, orthe like in a metallic housing, and each board is formed with an openingportion which is for lead-in or lead-out of outside line cables on theceiling side or the floor side of the housing.

The present invention improves installation workability, disasterprevention property, and seismic adequacy in the respective boards whichare arranged side by side and respective characteristic portions will bedescribed in the following.

Embodiment 1

Hereinafter, the enclosed switchboard of Embodiment 1 will be describedwith reference to drawings. FIG. 3 is a single line diagram forexplaining the configuration of the enclosed switchboard according toEmbodiment 1 of the present invention.

As shown in the drawing, a cable connection board 1, in which lead-incables and lead-out cables can be connected in one housing, and a devicecontaining board 2, in which main circuit devices such as circuitbreakers to be connected to the cable connection board 1 are contained,are arranged side by side. The configuration is made such that thedevice containing board 2 is ordinarily composed of a plurality ofboards and those boards are arranged side by side to one cableconnection board 1.

When FIG. 3 is compared to the aforementioned FIG. 1, the cableconnection board 1 corresponds to a cable connection board 100 of FIG. 1and the device containing board 2 corresponds to the circuit breakercontaining board 200 and subsequent boards.

FIG. 4 is a side view showing the internal structure of the cableconnection board 1 of the enclosed switchboard according toEmbodiment 1. The inside of a housing 3 is divided into two by apartition plate 6 to be comparted to a cable lead-in compartment 4 and acable lead-out compartment 5. The partition plate 6 is made of, forexample, a similar steel plate as the housing; however, an insulationplate may be used. A characterizing part of the present application isthat the structure is made such that, for example, even when the lead-inside is charged, work can be performed safely on the lead-out side bycompletely partitioning by the partition plate 6 and both compartmentsare contained in one housing 3. Incidentally, in the drawing, the leftis the front and the right is the back.

Lead-in side cables 7 for three phases are led in from a lead-in port 3a on the upper side of the cable lead-in compartment 4 and are supportedand fixed to a sidewall by a support member 8. Respective cableterminals and lead-in side main busbars 9 of three phases are connectedvia connection conductors 11 supported to the sidewall by supportinginsulators 10.

On the other hand, lead-out side cables 12 are led out from a lead-outport 3 b on the upper side of the cable lead-out compartment 5, andterminals of the lead-out side cables 12 and three phase lead-out sidemain busbars 13 are connected via connection conductors 14 supported tothe sidewall by the supporting insulators 10.

The cable lead-out compartment 5 takes a wider space than the cablelead-in compartment 4 and an arrangement path of the connectionconductors 14 is devised to make a phase sequence of the lead-in cablescoincide with that of the lead-out cables.

The lead-in port 3 a and the lead-out port 3 b for cables are bothprovided on the upper surface of the cable connection board 1 in FIG. 4;however, both ports may be provided on the lower surface of the cableconnection board 1 to lead in and lead out the cables from the lowerside. There is a case where the cables are disposed on the ceiling sideor are disposed in a pit on the floor side depending on buildingcircumstances in which the enclosed switchboard is installed; andtherefore, it may be appropriately selected so that a pull-around of thecables becomes easy depending on installation circumstances.

The arrangement of the main busbars to be connected to the cables isdetermined in accordance with the device arrangement of the devicecontaining board to be arranged side by side. In the case of thisembodiment, as to be described in the following, the lead-in side mainbusbars 9 are arranged in delta on the lower portion of the cablelead-in compartment 4 in accordance with the main busbar arrangement ofa circuit breaker containing board 2 (device containing board) whichcontains circuit breakers stacked in two stages; and thus, theconfiguration is made such that a space in the circuit breakercontaining board 2 is effectively used.

On the other hand, the lead-out side main busbars 13 are arranged to bedisposed in a vertical direction on the upper portion near the partitionplate 6 of the cable lead-out compartment 5.

Incidentally, the arrangement of the cable lead-in compartment 4 and thecable lead-out compartment 5 may be arranged with left-right reversaldepending on the inside configuration of the circuit breaker containingboard 2.

FIG. 5 is the device containing board which is arranged side by sideadjacently to the cable connection board 1 of FIG. 4. The circuitbreaker containing board 2 which contains the circuit breakers will bedescribed as an example of the device containing board. The drawing is aside view showing the internal structure thereof.

The inside of a housing of the circuit breaker containing board 2 iscomparted to a lower circuit breaker compartment 15 a and an uppercircuit breaker compartment 15 b from the lower side of the front (theleft side in the drawing) and the circuit breaker is contained in eachcompartment. The further upper side of the upper circuit breakercompartment 15 b is a controller compartment 16. The upper side of theback side is a lead-out side main busbar compartment 17 and the lowerside thereof is a lead-in side main busbar compartment 18. Eachcompartment is partitioned by a partition plate.

As shown by A in FIG. 5, three phase lead-in side main busbars 9 arearranged in a delta shape in the lead-in side main busbar compartment 18and are integrally connected with the lead-in side main busbar 9 of theaforementioned cable connection board 1 side.

Furthermore, as shown by B in FIG. 5, three phase lead-out side mainbusbars 13 are arranged in a vertical direction in the lead-out sidemain busbar compartment 17 and are integrally connected with thelead-out side main busbar 13 of the cable connection board 1 side.

The upper and lower circuit breakers are configured to be connected inseries between the lead-in side main busbars 9 and the lead-out sidemain busbars 13. Terminals for three phases of the circuit breakers aredisposed in a direction perpendicular to the page space and respectiveterminals are connected to the busbars of corresponding phases viabranch busbars 19.

Incidentally, the arrangement configuration of the main circuit devicesin the circuit breaker containing board 2 shows an example, but notlimited to FIG. 5.

As described above, according to the enclosed switchboard of Embodiment1, the enclosed switchboard includes: the device containing board whichcontains main circuit devices; and the cable connection board which isarranged side by side adjacently to the device containing board, andcontains cables that input and output electric power to/from the maincircuit devices. In the enclosed switchboard, the cable connection boardis configured by one housing; and the inside of the housing is dividedinto two by the partition plate to be comparted to the cable lead-incompartment which contains lead-in side cables and the cable lead-outcompartment which contains lead-out side cables; and therefore, thelead-in side cables and the lead-out side cables are contained in thesame housing. Consequently, as compared to the case where the lead-inside cable and the lead-out side cable are contained in individualhousings, cable connection processing can be performed in one side; andtherefore, connection work can be easily performed and the installationspace of the enclosed switchboard can be reduced.

Further, as compared to the conventional configuration in which thecable connection board is not provided and the box for connecting cablesare arranged on the upper portion of the housing of the enclosedswitchboard, the center of gravity of the whole board is lowered andthus aseismic performance is improved.

Besides, the lead-in port of the lead-in side cables and the lead-outport of the lead-out side cables are formed on either side of the uppersurface or the lower surface of the cable connection board.Consequently, a pull-around path of the cables can be selected inaccordance with circumstances of a placing location of the enclosedswitchboard; and therefore, the path is shortened and cable wiring canbe simplified.

Embodiment 2

FIG. 6 is a side view of a cable connection board of an enclosedswitchboard according to Embodiment 2 of the present invention and aview seen from the side opposite to the side to be connected to a devicecontaining board when arranged side by side. The inside configuration inthe board is equivalent to FIG. 4 of Embodiment 1; and therefore, thesame reference numerals and letters are given to equivalent portions andtheir description will be omitted.

As shown in the drawing, opening portions 20 a and 20 b capable ofperforming cable connection work are provided, respectively, in responseto portions where the cable lead-in compartment 4 and the cable lead-outcompartment 5 are arranged; and detachable working covers 21 a and 21 bare attached thereto.

In consideration of lead-in work of cables from the upper portion, thesize of the opening portions 20 a and 20 b is set from a portion near anupper end portion of the board to the vicinity of cable terminals atwhich cable connection processing is actually performed, which resultedin a size sufficient for performing visual confirmation during cableclamping work and inspection. Naturally, in the case where the lead-inand lead-out ports of the cables are located on the lower side, theopening portions 20 a and 20 b and working covers 21 a and 21 b areprovided at positions corresponding thereto.

The size of the working covers 21 a and 21 b and the opening portions 20a and 20 b is reduced to a range capable of performing connectioninspection work; and thus, the weight of the working covers 21 a and 21b can be reduced, thereby removing and attaching easily. Therefore,opening and closing become easier as compared to the case where thewhole door is opened and closed.

As described above, according to the enclosed switchboard of Embodiment2, the cable lead-in compartment and the cable lead-out compartment ofthe cable connection board are provided with the working opening portionand the working cover for covering the opening portion, respectively, ona surface opposite to the side facing the device containing board.Therefore, cable connection work can be easily performed, and confirmingwork and clamping work in periodic inspection or the like are also easyand thus workability is improved.

Embodiment 3

Next, an enclosed switchboard according to Embodiment 3 will bedescribed. This embodiment relates to the enclosed switchboard whichreduces damage due to fire and water disasters. The enclosed switchboardis a board corresponding to the feeder boards 300 and 400 in the unitconfiguration described in FIG. 1. In this regard, however, a devicearrangement of the inside shows an example, and the arrangement is notassumed to be directly connected to the circuit breaker containing board2 of Embodiment 1. Therefore, even when reference numerals and lettersof respective constituent elements are equivalent to those of Embodiment1, different reference numerals and letters are assigned thereto.

The enclosed switchboard in Embodiment 3 shown in FIGS. 7 to 10includes: air heat insulation layers A which block heat due to flameswhen a fire disaster occurs; and metallic barriers B which block flamesof the fire disaster generated in a main circuit of a drawing typecircuit breaker 40 to protect a control circuit. Relevant devices suchas the circuit breaker 40, the main circuit, and the control circuit arearranged at a higher level than an anticipated water intrusionwater-level. The specific location and the configuration of the air heatinsulation layers A and the metallic barrier B will be described later.FIG. 7A is a side sectional view and FIG. 7B is a back view.

In FIGS. 7A and 7B, a circuit breaker board U of the enclosedswitchboard includes circuit breaker compartments 32 stacked in stageson the front of a housing 31, a busbar compartment 33 provided on theback of the housing 31, a back compartment 34 composed of cablecompartments of an upper stage 34 a and a lower stage 34 b, and thelike. These compartments are arranged side by side in the housing 31;and, for example, the air heat insulation layers A for shielding heat,which block the heat due to flames when a fire disaster occurs, areformed at each portion of the respective compartments 32, 33, and 34.

Incidentally, the circuit breaker compartment 32 is a compartment inwhich the circuit breaker 40 and a control instrument 56 attached on theback of a front door 54 are contained and arranged in the inside; thebusbar compartment 33 is a compartment in which busbars 41 serving asthe main circuit are contained and arranged in the inside; and thebusbars 41 are connected to the respective circuit breakers 40.

Furthermore, the upper stage and lower stage cable compartments 34 a and34 b are compartments in which outside line cables for the main circuit42 serving as the main circuit are contained and arranged in the inside,and the outside line cables for the main circuit 42 are connected to therespective circuit breakers 40.

Further, the circuit breaker board U is arranged in plural rows in thehousing 31 and constitutes a part of the unit of the enclosedswitchboard.

The air heat insulation layers A have a function to block heat due toflames when a fire disaster occurs and are composed of the following: afirst air heat insulation layer 39 provided between both adjacent sidewalls of the circuit breaker boards provided in parallel; a second airheat insulation layer 35 provided on a ceiling portion of the uppercircuit breaker compartment 32; a third air heat insulation layer 36provided on a partition portion between the circuit breakers 40 stackedin stages, more specifically, between the upper and lower circuitbreaker compartments 32; a fourth air heat insulation layer 38 providedbetween the busbar compartment 33 and the back compartment 34 (not shownin the drawing) and on the partition portion between the cablecompartments of the upper stage 34 a and the lower stage 34 b; a fifthair heat insulation layer 37 provided on a back wall portion of thecircuit breaker compartment coming into contact with the busbarcompartment 33 and the back compartment 34, more specifically, providedbetween the circuit breaker compartment 32 and the back compartment 34.

Furthermore, the respective air heat insulation layers A (the first airheat insulation layer 39 to the fifth air heat insulation layer 37) areeach formed by the following member.

More specifically, the first air heat insulation layer 39 is formed bytwo partition plates between boards 39 a serving as both adjacent sidewalls; the second air heat insulation layer 35 is formed by forming aceiling plate 35 a in a double structure; the third air heat insulationlayer 36 is formed by a floor plate 44 (36 a of FIG. 7) for fixing thecircuit breakers and a cover 45 (36 a) clamped with bolts as shown inFIG. 8; the fourth air heat insulation layer 38 is formed by a partitionplate 38 a between the upper stage and lower stage cable compartments 34a and 34 b; and the fifth air heat insulation layer 37 is formed by twoback plates 37 a for fixing the circuit breakers between the front andback compartments.

In this manner, when a fire disaster occurs in any of a plurality ofcircuit breaker boards, heat due to flames is prevented from beingtransmitted and spread to the busbar compartment 33 on the back of thecircuit breaker board, the cable compartments of the upper stage 34 aand the lower stage 34 b, and the adjacent circuit breaker boards U byproviding the air heat insulation layers A on the respective portions asdescribed above. Further, a porcelain bushing 52 is attached to a busbarpass-through portion between the circuit breaker boards and thusindependent separation can be made for each circuit and separationperformance of the circuit breaker boards can be enhanced. Then, aseparation is also made between the circuit breaker boards U; and thus,the heat due to flames on the occurrence of fire disaster in the circuitbreaker board is prevented from being transmitted and spread to thebusbar compartment 33 on the back of the circuit breaker board, othercircuit breaker, other compartments 32 and 34, and the adjacent circuitbreaker boards U.

Incidentally, Embodiment 3 exemplifies the air heat insulation layers A;however, the heat insulation layer is not limited to a gas like air, anonflammable heat insulation material (glass wool, rock wool, or thelike) can also be used.

In FIGS. 8 to 10, the drawing type circuit breakers 40 stacked in upperand lower stages and contained in the circuit breaker compartment 32 areprovided with the metallic barriers B which block the controlinstruments 56 or the like from flames in the case of fire disaster; andthe metallic barriers B constitute an heat insulation mechanism by usingin combination with the air heat insulation layers A.

The metallic barriers B are composed of a first metallic barrier 46, asecond metallic barrier 47 (47 a, 47 b), and a third metallic barrier 48(48 a, 48 b).

The first metallic barrier 46 is a metallic barrier which is attached onthe housing 31 side between a circuit breaker arc extinction chamber 43and the front door 54 side.

The second metallic barrier 47 is composed of a metallic barrier 47 aattached on the housing 31 side and a metallic barrier 47 b attached tothe circuit breaker arc extinction chamber 43 side between the circuitbreaker arc extinction chamber 43 and a circuit breaker secondaryjunction 51.

The third metallic barrier 48 is composed of a metallic barrier 48 aattached to the housing 31 side and a metallic barrier 48 b attached tothe circuit breaker arc extinction chamber 43 side between a maincircuit terminal (not shown in the drawing) of the circuit breaker 40and the circuit breaker secondary junction 51.

A space is provided on the upper portion of a circuit breaker faceplate53 so that the metallic barrier 46 serving as the first metallic barrierdoes not interfere with the circuit breaker faceplate 53.

Furthermore, the second metallic barrier 47 composed of the metallicbarrier 47 a and the metallic barrier 47 b is provided in an upper spaceS1 between the circuit breaker arc extinction chamber 43 and the circuitbreaker secondary junction 51.

Further, the third metallic barrier 48 composed of the metallic barrier48 a and the metallic barrier 48 b is provided in a back space S2 formedon the back of the circuit breaker arc extinction chamber 43 between themain circuit terminal of the circuit breaker 40 and the secondaryjunction 51.

Besides, as shown in FIG. 8, the structure is made such that a slightgap is formed at a portion where the metallic barrier 47 a and themetallic barrier 47 b of the second metallic barrier 47 are overlappedwith each other and at a portion where the metallic barrier 48 a and themetallic barrier 48 b of the third metallic barrier are overlapped witheach other, so that flames are difficult to run round.

The main circuit of the circuit breaker 40 is separated from the controlcircuit by the metallic barrier B and thus the main circuit of thecircuit breaker can be separated from the control circuit; and when afire disaster occurs in the main circuit of the circuit breaker 40,flames are suppressed from being spread to the control circuit such asthe control instrument 56, the circuit breaker secondary junction 51,and control cables and damage can be prevented from being spread.

In the enclosed switchboard in Embodiment 3 shown in FIG. 7, therelevant devices such as the main circuit and the control circuit arearranged at a higher level than an anticipated water-level of waterintrusion in order to reduce damage in the case where water is intrudedinto the circuit breaker board U. More specifically, the drawing typecircuit breakers 40 are stacked in stages; the circuit breaker 40 of theupper stage, the busbar 41, the device to be contained, and insidemembers are arranged at a higher level; and control outside line cablesand the outside line cables 42 for the main circuit of the upper stagecircuit breaker are led out upward. Then, when the circuit stopped by afault is expected to be recovered promptly, the structure is made suchthat important circuits are arranged on the upper stage side and upperand lower stage circuits are completely partitioned and separated.Therefore, even when water is partially intruded into the circuitbreaker board U, if the water intrusion is under an upper limit 55 ofthe water-level capable of using the upper stage (a water-level at whichwater does not intrude into the busbar compartment 33), the structure ofthe board can be made such that the circuits on the upper stage side canbe promptly recovered without influence due to the water intrusion.

Embodiment 4

Hereinafter, Embodiment 4 will be described with reference to drawings.FIG. 11 is a perspective view of a housing for explaining the structureof a housing of an enclosed switchboard according to Embodiment 4; FIG.12 is a perspective view of a portion A of FIG. 11; FIG. 13 is aperspective view of a reinforcing member for use in a foundation fixingportion; and FIG. 14 is a perspective view showing a state where thereinforcing member is welded to FIG. 12.

The enclosed switchboard shown in FIG. 11 exemplifies the frameconfiguration of the board, which corresponds to, for example, the boardof FIG. 5 described in Embodiment 1. In this regard, however, thestructure of a foundation portion (to be described later) can be appliedto any of the cable connection board 100, the circuit breaker containingboard 200, or the feeder boards 300 and 400 of FIG. 1.

Incidentally, reference numerals and letters of respective portions aredifferent reference numerals and letters even if the respective portionsare equivalent to those of Embodiments 1 to 3.

An outline of the housing 61 of the enclosed switchboard is formed in asubstantially cuboid shape by appropriately combining a frame made of anangle steel or a channel steel, or a frame formed by bending a steelplate in an L-shape or a channel shape in cross section, or a frame thatdoubles as a side plate formed by bending both end portions of a widesteel plate, by welding, bolt clamping, or riveting so as to serve as avertical frame, a width directional frame, and a depth directionalframe. FIG. 11 shows an example thereof; and hereinafter, the structureof the housing will be described with reference to FIG. 11.Incidentally, for convenience of explanation, the description will bemade that the left side of FIG. 11 is regarded as the front side. Aleft-right direction seen from the front side is referred to as a widthdirection; and a front-back direction is referred to as a depthdirection.

A vertical frame 62 that doubles as a side plate formed by bending bothend portions of a thin steel plate is arranged in a standing conditionon the left and the right of the front side, a vertical frame 63 formedby bending in a channel shape in cross section is arranged in a standingcondition on the left and the right of the back side, and the verticalframes 62 and 63 are integrally combined by width directional frames 64and 65 connecting the left and the right and by depth directional frames66 connecting the front and the back. Depending on the configuration andthe size of devices to be contained in the switchboard, the widthdirectional frames and the depth directional frames are alsoappropriately provided at intermediate portions in a vertical direction,and the vertical frames are also appropriately provided at intermediateportions in the depth direction; however the drawing is typified byreference numeral 64 to 66.

Incidentally, the number and the shape of the respective frames of FIG.11 show an example, but not limited to the shape of the drawing.

Furthermore, when the housing 61 receives vibrations due to anearthquake or the like, the housing 61 is welded with a reinforcementplate 67 formed, for example, in a triangle shape at a portion wherehousing frames of weak strength are butted at a right angle, in order toprevent the switchboard from being deformed and to enhance theearthquake-resistance strength of the whole switchboard. Further, thefloor side of the housing 61 is configured so as to be able to be fixedby foundation bolts (as to be described later) so that the housing 61does not fall down by an earthquake or the like. Such a fixing deviceportion has the characteristics of this embodiment and therefore thefixing device portion will be described later.

FIG. 12 is an enlarged view of a portion A of FIG. 11 and shows a statebefore a reinforcing member (to be described later) is attached. Thevertical frame 62 for doubling as the side plate is formed by bendingthe front side of a plate material in a channel shape and doubles as afront vertical frame and the side plate. A floor plate 68 is formed bybending the front side in an L-shape and also doubles as a front widthdirectional frame. Vertical frames 69 arranged in face-to-face relationon the left and the right of the housing 61 are provided on the moreback side than the front; and a floor width directional frame 70 isprovided so as to connect the lower sides of the left and right verticalframes 69. The floor plate 68 is formed with a through hole 68 a havingan outer diameter larger than a hole for foundation 71 a at a positioncorresponding to the hole for foundation 71 a formed in a reinforcingmember 71 (to be described next).

Incidentally, in addition to the vertical frame 62 doubling as the sideplate as shown in the drawing, a vertical frame formed in an L-shape, achannel shape, or a hollow rectangular shape in cross section may beused on the left and the right of the front side; and a horizontal frameof a different member may also be used on the front side of the floorplate 68.

FIG. 13 is a perspective view showing the reinforcing member 71. Thereinforcing member 71 is made of thick steel plate that is sufficientlythicker than the thickness of a member constituting each frame, and thelength of the reinforcing member 71 is a length fitted to the inside ofthe left and right vertical frames or the side plates of the housing 61without a substantial gap. Furthermore, the holes for foundations 71 aare formed near length directional both end portions. Incidentally, theshape of cutout portions 71 b formed on both end portions is differentin accordance with the shape of the vertical frames to be combined.

FIG. 14 is a perspective view showing a state where the reinforcingmember 71 of FIG. 13 is combined with a frame structure shown in FIG.12. The reinforcing member 71 having a large thickness is mounted on thefloor plate 68, both ends in the length direction of the reinforcingmember 71 are come into contact with the lower insides of the verticalframes 62 doubling as the left and right side plates of the housing 61and the lower sides of the vertical frames 69, and lateral faces of thereinforcing member 71 are come into contact with the frame portion ofthe front side of the floor plate 68 and the floor width directionalframe 70; and the thus configured structure is fixed by welding.

Incidentally, the entire periphery of the butted portions does not needto be welded, but intermittent welding may be permissible as shown inthe drawing as welding portions 72.

Furthermore, in FIG. 14, the reinforcing member 71 is welded at itsfront and back lateral faces to the front frame portion of the floorplate 68 and the floor width directional frame 70; however, thearrangement of the frame is non-uniform and therefore at least one ofthe lateral faces may be fixed to the width directional frame.

FIG. 12 to FIG. 14 describe about the reinforcing member 71 provided onthe lower portion of the front side of the housing 61. However, thereinforcing member 71 is a member for fixing the housing 61 to thefoundation surface; and therefore, the reinforcing member 71 is alsoprovided on the lower portion of the back side as shown in FIG. 11.

Further, when the housing 61 is increased in size and the number of thedevices to be contained is increased, loads of the circuit breakers andthe like to be contained are applied on a depth directional intermediateportion; and therefore, as shown in FIG. 11, the configuration is madesuch that the similar reinforcing member 71 is provided in accordancewith the vertical frames at the depth directional intermediate portionsand the floor width directional frame at a position correspondingthereto, and the holes for foundation are formed near length directionalboth end portions of the reinforcing member 71 so as to be fixed by thefoundation bolts.

FIG. 15 is a sectional view in the case of fixing to the foundationusing a foundation bolt 73 from the upper side of the reinforcing member71. An embedded metal (not shown in the drawing) having a female screwto be adapted to a male screw of the foundation bolt 73 is embedded inthe foundation surface side. As shown in the drawing, fixing is made byclamping the foundation bolt 73 via a flat washer 74.

FIG. 16 is the case where an anchor bolt 75 is preliminarily embedded ata predetermined position of the foundation surface. The housing 61 isinstalled to the foundation surface in accordance with the anchor bolt75, a nut 76 is clamped via the flat washer 74, and the housing 61 isfixed by fixing the reinforcing member 71 to the foundation surface.

Next, the action of the reinforcing member 71 will be described.

As described above, the reinforcing member 71 is made of a thick platethat is thicker than the thickness of the surrounding frames fixedthereto, and is provided over the whole width directional length of thehousing 61. Therefore, rigidity of a floor of the enclosed switchboardcan be enhanced; and even if such a large force as to shake the housing61 by an earthquake or the like is exerted, a fixing portion of thefloor of the housing 61 can be prevented from being deformed.

Furthermore, the reinforcing member 71 is provided over the whole widthdirectional length of the housing 61 and the holes for foundation 71 aare formed near the length directional both end portions of thereinforcing member 71. Therefore, a pair of the holes for foundation 71a are formed on the same member; and thus, for example, as compared tothe case where the individual reinforcing member is welded on the leftand the right of the housing as disclosed in Patent Document 4, adimension between the pair of the holes for foundation 71 a can beprocessed with high accuracy at a manufacturing stage of the reinforcingmember 71. For this reason, the dimension between the bolts does notneed to be adjusted later; and therefore, welding work and siteinstallation work of the housing 61 become easy. Furthermore, the numberof components can also be reduced.

Further, dimensional accuracy between the holes of the pair of the holesfor foundation 71 a formed in the reinforcing member 71 is enhanced ascompared to the individual case; and thus, the hole diameter of the holefor foundation 71 a does not need to be a large hole in anticipation ofa dimensional error and the hole can be, for example, a standard bolthole specified by standards. By this, a large diameter and thick specialwasher does not need to be used at a bolt clamping portion; and evenwhen a standard flat washer of a generally used standardized article isused, it becomes possible to maintain high rigidity of the bolt clampingportion.

Incidentally, dimensions of the holes for foundation 71 a formed in therespective reinforcing members 71 of the front side and the back side(or the intermediate portion) are severe to enhance dimensional accuracybecause of different members as compared to the left and right holes forfoundation 71 a; however, even in this case, as compared to the case ofindividual four corners like Patent Document 4, dimensional accuracy iseasier to enhance. Furthermore, the hole for foundation 71 a is not around hole, but may be a long hole that is long in the front-backdirection.

As described above, according to the enclosed switchboard of Embodiment4, the enclosed switchboard includes the housing whose outline is formedin the substantially cuboid shape by combining the vertical frames, thewidth directional frames, and the depth directional frames. In theenclosed switchboard, the housing includes: a pair of vertical framesarranged in face-to-face relation on the left and the right in the widthdirection of the housing; the floor side width directional frameprovided so as to connect the lower sides of the vertical frames; andthe reinforcing member for fixing the housing. The reinforcing member ismade of a plate thicker than the thickness of each of the frames and hasa length whose both ends come into contact with the pair of the verticalframes, and the reinforcing member is arranged on the floor plate of thehousing and fixed to the lower side of the pair of the vertical framesand the floor side width directional frame by welding. Consequently,rigidity of the floor of the enclosed switchboard can be enhanced andthe enclosed switchboard excellent in seismic adequacy can be provided.

Moreover, the reinforcing member is provided on the front side, the backside, and the intermediate portion in the depth direction of thehousing, whereby, in addition to rigidity of the front and the back ofthe housing, rigidity of the floor at the intermediate portion to whichmany loads of the devices to be contained in the switchboard areapplied, is enhanced and therefore the enclosed switchboard excellent inseismic adequacy can be obtained.

Furthermore, the hole for foundation, which is for fixing thereinforcing member to the foundation surface, is provided near lengthdirectional both end portions of the reinforcing member, whereby adimension between the holes for foundation in the left-right directionof the housing can be formed with high accuracy and therefore weldingwork and site installation work of the housing become easy.

Further, the size of the hole for foundation is that of the bolt hole ofstandards corresponding to the foundation bolt to be used, whereby aspecial washer does not need to be used at the bolt clamping portion anda standard flat washer of a standardized article can be used.

Incidentally, in the present invention, the respective embodiments canbe freely combined and appropriately changed or omitted within the scopeof the present invention.

EXPLANATIONS OF LETTERS OR NUMERALS

-   -   1 Cable connection board    -   2 Device containing board (Circuit breaker containing board)    -   3 Housing    -   3 a Lead-in port    -   3 b Lead-out port    -   4 Cable lead-in compartment    -   5 Cable lead-out compartment    -   6 Partition plate    -   7 Lead-in side cable    -   8 Support member    -   9 Lead-in side main busbar    -   10 Supporting insulator    -   11, 14 Connection conductor    -   12 Lead-out side cable    -   13 Lead-out side main busbar    -   15 a Lower circuit breaker compartment    -   15 b Upper circuit breaker compartment    -   16 Controller compartment    -   17 Lead-out side main busbar compartment    -   18 Lead-in side main busbar compartment    -   19 Branch busbar    -   20 a, 20 b Opening portion    -   21 a, 21 b Working cover    -   31 Housing    -   32 Circuit breaker compartment    -   33 Busbar compartment    -   34 Back compartment    -   34 a Upper stage cable compartment    -   34 b Lower stage cable compartment    -   35 Second air heat insulation layer    -   35 a Ceiling plate    -   36 Third air heat insulation layer    -   36 a Partition plate    -   37 Fifth air heat insulation layer    -   37 a Back plate    -   38 Fourth air heat insulation layer    -   38 a Partition plate    -   39 First air heat insulation layer    -   39 a Partition plate between boards    -   40 Circuit breaker    -   41 Busbar    -   42 Outside line cables for main circuit    -   43 Circuit breaker arc extinction chamber    -   44 Floor plate for fixing circuit breaker    -   45 Cover clamped with bolts    -   46 First metallic barrier    -   47 Second metallic barrier (47 a, 47 b)    -   48 Third metallic barrier (48 a, 48 b)    -   51 Circuit breaker secondary junction    -   52 Porcelain bushing    -   53 Circuit breaker faceplate    -   54 Front door    -   55 Upper limit of water-level capable of using upper stage side        circuit in case of water intrusion into circuit breaker board    -   56 Control instrument    -   A Air heat insulation layer    -   B Metallic barrier    -   S1 Upper space    -   S2 Back space    -   U Circuit breaker board    -   61 Housing    -   62, 63, 69 Vertical frame    -   64, 65 Width directional frame    -   66 Depth directional frame    -   67 Reinforcement plate    -   68 Floor plate    -   68 a Through hole    -   70 Floor width directional frame    -   71 Reinforcing member    -   71 a Hole for foundation    -   71 b Cutout portion    -   72 Welding portion    -   73 Foundation bolt    -   74 Flat washer    -   75 Anchor bolt    -   76 Nut    -   100 Cable connection board    -   200 Circuit breaker containing board    -   300, 400 Feeder board

1. An enclosed switchboard comprising a housing whose outline is formedin a substantially cuboid shape by combining vertical frames, widthdirectional frames, and depth directional frames, wherein said housingincludes: a pair of vertical frames arranged in face-to-face relation onthe left and the right in the width direction of said housing; a floorside width directional frame provided so as to connect the lower sidesof said vertical frames; and a reinforcing member for fixing saidhousing, said reinforcing member being made of a plate thicker than thethickness of each of said frames and having a length whose both endscome into contact with the pair of said vertical frames, and saidreinforcing member being arranged on a floor plate of said housing andfixed to the lower sides of the pair of said vertical frames and saidfloor side width directional frame by welding.
 2. The enclosedswitchboard according to claim 1, wherein said reinforcing member isprovided on the front side, the back side, and an intermediate portionin a depth direction of said housing.
 3. The enclosed switchboardaccording to claim 1, wherein a hole for foundation, which is for fixingsaid reinforcing member to a foundation surface, is provided near lengthdirectional both end portions of said reinforcing member.
 4. Theenclosed switchboard according to claim 3, wherein the size of the holefor foundation is that of a bolt hole of standards corresponding to afoundation bolt to be used.
 5. The enclosed switchboard according toclaim 2, wherein a hole for foundation, which is for fixing saidreinforcing member to a foundation surface, is provided near lengthdirectional both end portions of said reinforcing member.